U.S. patent number 7,275,957 [Application Number 11/277,164] was granted by the patent office on 2007-10-02 for axial compression electrical connector for annular corrugated coaxial cable.
This patent grant is currently assigned to Andrew Corporation. Invention is credited to John Dykstra, Joon Lee, Jeffrey Paynter, James J. Wlos.
United States Patent |
7,275,957 |
Wlos , et al. |
October 2, 2007 |
Axial compression electrical connector for annular corrugated
coaxial cable
Abstract
An electrical connector having a longitudinal axis with
interface and cable ends for coaxial cable having an annular
corrugated solid outer conductor. The connector having a body and
an interface joined in an interference fit along the longitudinal
axis of the connector. A spring finger ring within a bore of the
body is rigidly connected to the body. The spring finger ring
having a plurality of spring fingers extending towards an connector
end; the spring fingers having an inward projecting bead at the
connector end. The spring fingers positioned opposite an outer
conductor groove open to the cable end, the outer conductor groove
proximate the cable end of the interface.
Inventors: |
Wlos; James J. (Crete, IL),
Dykstra; John (Tinley Park, IL), Lee; Joon (Bolingbrook,
IL), Paynter; Jeffrey (Momence, IL) |
Assignee: |
Andrew Corporation
(Westchester, IL)
|
Family
ID: |
38055214 |
Appl.
No.: |
11/277,164 |
Filed: |
March 22, 2006 |
Current U.S.
Class: |
439/583 |
Current CPC
Class: |
H01R
9/0527 (20130101); H01R 24/564 (20130101); H01R
2103/00 (20130101) |
Current International
Class: |
H01R
9/05 (20060101) |
Field of
Search: |
;439/583,584,578,429 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Patel; Tulsidas C.
Assistant Examiner: Nguyen; Phuongchi
Attorney, Agent or Firm: Babcock IP, PLLC
Claims
The invention claimed is:
1. An electrical connector, having a longitudinal axis with an
connector end and a cable end, for annular corrugated solid outer
conductor coaxial cable, comprising: a body and an interface joined
in an interference fit along the longitudinal axis of the
connector; a spring finger ring within a bore of the body, rigidly
connected to the body; the spring finger ring having a plurality of
spring fingers extending towards the connector end; the spring
fingers having an inward projecting bead at the connector end; and
a flare ring within the bore having a retaining lip and a flare
seat forming an outer conductor groove open to the cable end, the
flare ring abutting the cable end of the interface.
2. The connector of claim 1, wherein the flare ring is retained
abutting the cable end of the interface by a preliminary
interference fit against the bore of the body.
3. The connector of claim 1, further including a center pin
coaxially supported within a bore of the interface by an insulator,
the center pin having a spring basket at the cable end.
4. The connector of claim 1, further including an interface gasket
groove in the bore of the body, between the interference fit of the
body and the interface.
5. The connector of claim 1, further including a coupling nut
rotatably retained upon an outer diameter of the interface by a
retention shoulder at the connector end and by the body at the
cable end.
6. The connector of claim 5, wherein the coupling nut is formed
from a metallic coupling nut inner portion and a polymeric coupling
nut overmolding covering an outer diameter, the cable end and the
connector end.
7. The connector of claim 1, wherein the body is formed from a
metallic body inner portion and a polymeric body overmolding
covering an outer diameter, the cable end and the connector
end.
8. The connector of claim 7, wherein the body overmolding extends
from the cable end of the body along the longitudinal axis, the
bore continuing through the overmolding having a guide surface with
an increasing inner diameter towards the cable end.
9. An electrical connector, having a longitudinal axis with an
connector end and a cable end, for annular corrugated solid outer
conductor coaxial cable, comprising: a body and an interface joined
in an interference fit along the longitudinal axis of the
connector; a spring finger ring within a bore of the body, rigidly
connected to the body; the spring finger ring having a plurality of
spring fingers extending towards the connector end; the spring
fingers having an inward projecting bead at the connector end; and
a retaining lip and a flare seat forming an outer conductor groove
open to the cable end; the outer conductor groove proximate the
cable end of the interface.
10. The connector of claim 9, wherein via application of an axial
compression force between the cable end and the connector end along
the longitudinal axis, the body and the interface are movable along
the interference fit to clamp a leading edge of the solid outer
conductor between the spring fingers and the outer conductor
groove.
11. The connector of claim 9, wherein the body has a metallic body
inner portion with a bore and a polymeric body overmolding covering
an outer diameter of the body inner portion; the body overmolding
extending from the cable end of the body along the longitudinal
axis, the bore extending from the body through the body overmolding
and having a guide surface with an increasing inner diameter
towards the cable end.
12. The connector of claim 9, wherein the outer conductor groove is
formed in a flare ring adjacent to the cable end of the
interface.
13. The connector of claim 9, wherein the outer conductor groove is
formed in a flare ring adjacent to the cable end of the interface;
the flare ring having a preliminary interference fit against the
bore.
14. The connector of claim 9, wherein the cable is insertable
within the bore from the cable end; the spring fingers deflectable
to allow passage of a leading edge of the solid outer conductor
past the inward projecting bead(s).
15. The connector of claim 9, further including a center pin
coaxially supported within a bore of the interface by an insulator,
the center pin having a spring basket at the cable end.
16. The connector of claim 9, wherein the rigid connection between
the spring finger ring and the body is via an interference fit.
17. The connector of claim 9, further including an interface gasket
groove formed in the bore of the body between the cable end and the
connector end of the interference fit.
18. The connector of claim 9, further including a coupling nut
rotatably retained upon an outer diameter of the interface by a
retention shoulder at the connector end and the connector end of
the body.
19. The connector of claim 18, wherein a maximum outer diameter of
the body is less than a maximum outer diameter of the coupling
nut.
20. An electrical connector, having a longitudinal axis with an
connector end and a cable end, for annular corrugated solid outer
conductor coaxial cable, comprising: a body having a metallic body
inner portion with a bore and a polymeric body overmolding covering
an outer diameter, the cable end and the connector end of the body
inner portion; the body overmolding extending from the cable end of
the body along the longitudinal axis, the bore extending from the
body through the body overmolding having a guide surface with an
increasing inner diameter towards the cable end; an interface
joined in an interference fit with the body along the longitudinal
axis of the connector; a coupling nut rotatably retained upon an
outer diameter of the interface by a retention shoulder at the
connector end and by the body at the cable end; the coupling nut
having a metallic coupling nut inner portion and a polymeric
coupling nut overmolding covering an outer diameter of the coupling
nut inner portion, the cable end and the connector end of the
coupling nut inner portion; a spring finger ring within the bore of
the body, rigidly connected to the body; the spring finger ring
having a plurality of spring fingers extending towards an connector
end; the spring fingers having an inward projecting bead at the
connector end; and a flare ring within the bore having a retaining
lip and a flare seat forming an outer conductor groove open to the
cable end, the flare ring abutting the cable end of the interface,
retained by a preliminary interference fit against the bore of the
body.
Description
BACKGROUND OF INVENTION
1. Field of the Invention
The invention relates to an electrical connector. More particularly
the invention relates to an electrical connector installable upon
an electrical cable having an annular corrugated outer conductor by
application of axial compression without disassembly of the
connector.
2. Description of Related Art
Connectors for corrugated outer conductor cable are used throughout
the semi-flexible corrugated coaxial cable industry.
Previously, connectors have been designed to attach to annular
corrugation outer conductor coaxial cable using mechanical
compression via threaded connections between a body and an
interface operable to clamp a leading edge of the outer conductor.
Typically, the clamping is made against a clamping surface of the
interface that is beveled to match the angle of a flared leading
edge of the outer conductor. Clamping the leading edge of the outer
conductor against the clamping surface is a thrust washer or the
like, usually disassociated from the body to prevent twisting or
tearing of the leading edge(s) of the outer conductor and or spring
finger(s) as the body and interface are rotated with respect to
each other.
Spring finger rings with a plurality of spring fingers tipped with
an inward projecting bead at the end of each spring finger have
been used as the thrust washer. The spring fingers deflecting over
the leading edge of the outer conductor and settling into the first
corrugation trough, where the inward projecting beads can then
clamp against the back side of the outer conductor leading edge. To
allow the spring finger ring to be rotationally disassociated from
the body, a series of retaining grooves, steps and or shoulders
have previously been applied, resulting in a connector requiring
extensive machining steps during manufacture and having a
significantly increased body diameter and overall weight.
Competition within the cable and connector industry has increased
the importance of minimizing installation time, required
installation tools, and connector manufacturing/materials costs.
Also, competition has focused attention upon ease of use,
electrical interconnection quality and connector reliability.
Therefore, it is an object of the invention to provide an
electrical connector and method of installation that overcomes
deficiencies in such prior art.
BRIEF DESCRIPTION OF DRAWINGS
The accompanying drawings, which are incorporated in and constitute
a part of this specification, illustrate embodiments of the
invention and, together with a general description of the invention
given above, and the detailed description of the embodiments given
below, serve to explain the principles of the invention.
FIG. 1 is an external isometric view of a connector according to a
first embodiment of the invention.
FIG. 2 is a cable end view of FIG. 1.
FIG. 3 is a combination external side view and partial cross
sectional view of FIG. 1, along line A-A.
FIG. 4 is a cable end isometric view of a spring finger ring.
FIG. 5 is a cross sectional side view of FIG. 4.
FIG. 6 is a combination external side view and partial cross
sectional view of FIG. 1, along line A-A, after coaxial cable
insertion and before axial compression.
FIG. 7 is a combination external side view and partial cross
sectional view of FIG. 1, along line A-A, after coaxial cable
insertion and axial compression.
DETAILED DESCRIPTION
The inventor(s) have recognized that the prior threaded spring
finger connectors require extensive machining operations upon the
body, interface and thrust washer or spring finger ring during
manufacture to generate the interconnection threads and or multiple
guide grooves/steps and or shoulders which rotatably retain the
thrust washer or spring finger ring within the body.
Also, the inventors have recognized that prior connectors have
typically been machined from solid metal bar stock resulting in
significant materials costs. Expanded connector body dimensions
required to provide suitable tightening tooling surfaces, strength
for threaded interconnect surfaces as well as to rotatably enclose
the thrust washer, spring finger ring or the like further increases
the materials requirements and installation difficulties.
The invention will be described in detail with respect to FIGS. 1-7
in a standard Type-N connector interface for use with annular
corrugated solid outer conductor coaxial cable. One skilled in the
art will appreciate that the invention, as will be discussed herein
below, is similarly applicable to other standard or proprietary
connector interface(s).
A connector 1 comprises a coupling nut 3 surrounding an interface 5
which mates to a body 7. To reduce metal materials requirements and
decrease the overall weight of the connector 1, the body 7 may be
formed with a body inner portion 9 and a body overmolding 11.
Similarly, the coupling nut 3 may be formed with a coupling nut
inner portion 13 and a coupling nut overmolding 14. The body and
coupling nut overmolding(s) 11, 14 may be a polymeric material such
as polycarbonate or other plastic injection molded about the
corresponding inner portion. A textured surface treatment 16 may be
applied to the metal inner body and coupling nut portions 9, 13 to
improve adhesion with the overmolding.
As shown in FIG. 3, a connector 1 according to the invention is
ready for installation upon a cable 15 without any
assembly/disassembly requirements. The body inner portion 9 and
interface 5 are coupled together in an interference fit along the
connector end 17 bore of the body inner portion 9 and a
corresponding cable end 19 outer diameter of the interface 5.
Within the connector 1 a flare ring 21 is retained by an initial
interference fit within the body 7 and adjacent to a cable end 19
of the interface 5. The flare ring 21 has a beveled flare seat 23
and a retaining lip 25 that form an outer conductor groove 27 open
to the cable end 19 of the connector 1. Alternatively, the beveled
flare seat 23 and retaining lip 25 that form the outer conductor
groove 27 may be formed in the cable end of the interface 5,
eliminating the flare ring 21.
A spring finger ring 29, for example as shown in FIGS. 4 and 5, is
located within the body 7 bore coupled to the cable end 19 of the
body inner portion 9. The spring finger ring 29 has a plurality of
spring finger(s) 31 extending towards the connector end 17. Each of
the spring finger(s) 31 has an inward projecting bead 33 at the
tip. The body overmolding 11 at the cable end 19 may be formed
extending inward to an inner radius of the spring finger ring 29
assisting with the retention of the spring finger ring 29 within
the body inner portion 9 bore. Also, an angled face formed in the
body overmolding 11 at the cable end 19 may provide a guide surface
35 for the insertion of the cable 15 into the connector 1.
The interface 5 is adapted according to the type of connection
interface desired. If needed, an insulator 37 may be used to retain
a center pin 39 coaxially within the interface 5. A spring basket
41 at the cable end 19 of the center pin 39 is inwardly biased to
electrically contact and retain an inner conductor 41 of the cable
15 upon insertion.
The coupling nut 3 is rotatably retained around the outer diameter
of the interface 5 between an outwardly projecting retention
shoulder 45 at the connector end 17 and the body 7 at the cable end
19. In the first embodiment, the coupling nut inner portion 13 is
threaded according to the specification of the Type N
interface.
A connector 1 according to the invention is mounted according to
the following procedure. A coaxial cable 15 is stripped back to
expose the desired length of inner conductor 43 from the outer
conductor 47 and the outer sheath 49, if any, is removed from a
desired length of the outer conductor 47. The cable 15 is then
inserted into the cable end 19 of the connector 1. Because the
flare ring 21 is retained adjacent the cable end 19 of the
interface 5 by the initial interference fit with the inner body
portion 9, as a leading edge 51 of the outer conductor 47 contacts
the inward projecting bead(s) 33 of the spring finger(s) 31, the
spring finger(s) 31 are clear of the flare ring 21 retaining lip
25, allowing the spring finger(s) 31 to be deflected outwards to
allow the leading edge 51 of the outer conductor 47 to pass. As
shown in FIG. 6, as the leading edge 51 of the outer conductor 57
passes the inward projecting bead(s) 33 of the spring finger(s) 31,
the spring finger(s) 31 return to a ready state, resting in the
first corrugation behind the leading edge 51 of the outer conductor
47. At the same time, as shown in FIG. 6, the inner conductor 43
has been advanced to a position just short of entry into the spring
basket 41 of the center pin 39, if present.
To finally secure the connector 1 and cable 15 together, axial
compression is applied. An axial compression tool is attached,
abutting the cable end 19 of the body 7. The axial compression tool
is used to apply an axial compression force between the cable end
19 of the connector 1 and the interface 5, along the longitudinal
axis of the connector 1 and cable 15. As the axial compression
force is applied, the preliminary interference fit between the
interface 5 and the body 7 shifts to move the interface 5 and the
flare ring 21 abutting the interface 5 towards the cable end 19,
into a final interference fit. As the body and interface move
relative to one another the retaining lip 25 of the flare ring 21
moves towards and overlaps the connector end 17 of the spring
finger(s) 31 preventing deflection up and away from the leading
edge 51 and or flare seat 23. Thus, the cable 15 is retained within
the bore by the spring fingers. As the flare ring 21 moves towards
the cable end 19, the leading edge 51 of the outer conductor 47
engages the flare seat 23 and is flared up and away from the inner
conductor 43 along the flare seat 23. Insulation 53 between the
inner and outer conductor(s) 43, 47 of the cable 15 is deformed
downward and away from the outer conductor 47 providing a metal to
metal contact between the flare seat 23 and the leading edge 51 of
the outer conductor 47 around a 360 degree circumference. At the
same time, the inner conductor 43 is advanced into the spring
basket 41 of the center pin 39, creating a secure connection
between the inner conductor 43 and the center pin 39.
As shown in FIG. 7, when the axial compression is complete, the
interference fit between the body 7 and the interface 5 has been
shifted such that the flare ring 21 and spring finger(s) 31 are
securely clamped against front and back sides of the flared leading
edge 51 of the outer conductor 47 and the inner conductor 43 is
securely retained within the spring basket 41 of the center pin 39,
if present. The body 7 has moved closer to the coupling nut 3, but
still leaves enough room for the coupling nut 3 to be rotatable for
interconnection with a desired connection interface.
A plurality of compressible and or deformable sealing gaskets, for
example rubber or silicon o-rings, may be located around and within
the connector 1 to environmentally seal the connecting surface(s).
An connector interface gasket 55 may be located seated upon the
interface 5, to seal an interconnection between the connector 1 and
a mating connector. An interface gasket groove 57 may be formed,
for example along a bore of the body 7 to seat a gasket (not shown)
to seal the interference fit between the interface 5 and the body
7. Also, a cable gasket (not shown) may be seated in a
corresponding annular corrugation of the outer conductor 43 between
the body overmolding 11 and the outer conductor 47.
Upon a review of this Specification, one skilled in the art will
appreciate that the various interference fit surfaces described
herein may be oriented in alternative overlapping surface
configurations. Further, the connector interface may be a
proprietary configuration or a standard interface, for example,
Type F, SMA, DIN, Type N or BNC. Also, additional features may be
included, for example, to provide seating surfaces for specific
axial compression apparatus.
The invention provides an environmentally sealed connector 1 with
improved installation characteristics. Depending upon the material
characteristics and dimensions of the particular cable 15 used, the
connector 1 may be quickly and securely attached using a compact
hand tool. Because threading between the body 7 and interface 5 has
been eliminated by configuration for mounting via axial
compression, the body 7 and interface 5 do not need to be sized to
support exterior wrench flats and or threads between the interface
5 and the body 7. Therefore, even with larger diameter cable(s) 15,
the largest body 7 diameter may be easily configured to be less
than the largest coupling nut 3 diameter which enables the
installation of connectors and cables according to the invention in
small spaces and or alongside each other in closer proximity.
Because the factory pre-assembled connector 1 does not require any
disassembly or other preparation before mounting upon a cable, the
opportunity for losing or damaging an essential part of the
connector 1 has been eliminated. In addition to reduced wall
thickness requirements, through the application of overmolded
polymeric outer surfaces and body 7 extensions, the connector 1 has
significantly reduced weight.
The invention also provides significant manufacturing and materials
cost efficiencies. The application of polymeric overmolding for
outer surfaces significantly reduces the metal content of the
connector 1 while the inner portions of the body 7 and coupling nut
3 maintain a fully contiguous metallic electrical enclosure with
suitable levels of strength. Because the invention applies axial
compression to attach the connector 1 to a cable, threading is
eliminated with respect to the clamping of the outer conductor.
This allows the spring finger ring 29 to be permanently mounted
within the body 7 without rotatability, greatly reducing the number
of threading, shoulder, step and or groove machining steps required
during manufacture. Further, the greatly simplified surfaces of the
body 7, interface 5 and or spring finger ring 29 according to the
invention creates an opportunity for connector 1 component
manufacture using cost effective metal injection molding
technologies.
TABLE OF PARTS
1 connector 3 coupling nut 5 interface 7 body 9 body inner portion
11 body overmolding 13 coupling nut inner portion 14 coupling nut
overmolding 15 cable 16 surface treatment 17 connector end 19 cable
end 21 flare ring 23 flare seat 25 retaining lip 27 outer conductor
groove 29 spring finger ring 31 spring finger 33 inward projecting
bead 35 guide surface 37 insulator 39 center pin 41 spring basket
43 inner conductor 45 retention shoulder 47 outer conductor 49
sheath 51 leading edge 53 insulation 55 connector interface gasket
57 interface gasket groove
Where in the foregoing description reference has been made to
ratios, integers or components having known equivalents then such
equivalents are herein incorporated as if individually set
forth.
While the present invention has been illustrated by the description
of the embodiments thereof, and while the embodiments have been
described in considerable detail, it is not the intention of the
applicant to restrict or in any way limit the scope of the appended
claims to such detail. Additional advantages and modifications will
readily appear to those skilled in the art. Therefore, the
invention in its broader aspects is not limited to the specific
details, representative apparatus, methods, and illustrative
examples shown and described. Accordingly, departures may be made
from such details without departure from the spirit or scope of
applicant's general inventive concept. Further, it is to be
appreciated that improvements and/or modifications may be made
thereto without departing from the scope or spirit of the present
invention as defined by the following claims.
* * * * *